1. Field of the Invention
The ivention relates to a method and apparatus for the microwave joining of two materials, particularly nonoxide ceramic items.
2. Description of the Related Art
The bonding together of ceramic materials is generally accomplished by many different methods and apparatuses. Exemplary methods and apparatuses are shown and described in U.S. Pat. Nos. 4,384,909, 4,347,089, 3,998,632, 3,841,870, and 3,755,065.
Other methods and apparatuses for bonding together two difficult materials by the application of microwave energy are disclosed in U.S. Pat. Nos. 4,273,950, 4,219,361, 4,179,596, and 4,003,368.
Methods and apparatuses for the microwave joining of ceramic items are specifically described in U.S. Pat. Nos. 4,529,857, 4,529,856, 4,307,277, 4,292,262, 4,147,911, 3,953,703, 3,732,048, 3,585,258, and 3,520,055.
Prior art apparatuses for making joints between ceramic materials using microwave energy have sometimes employed ovens conventionally used for cooking food. In such ovens, the microwave field exists in many different orientations and power supplied to the oven is distributed accordingly. Not all of these orientations or modes couple efficiently to the ceramic items being joined. Furthermore, no methods and apparatuses in the prior art are known to simultaneously apply compressive forces to nonoxide ceramic items in either a vacuum or an atmosphere overpressurized with inert gas in order to stimulate and enhance the joining together of such items and to continuously monitor the joint being formed between the two nonoxide ceramic items in such vacuum or overpressurized atmosphere in order to assure a good bond.